Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC B3125 00: Left Front/Driver Door Only Unlock CircuitDTC B3130 00: All Door Unlock Circuit
DTC B3135 00: All Door Lock Circuit
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Driver Door Lock Switch Lock Signal | B3150 00 | 1 | 1 | -- |
Driver Door Lock Switch Unlock Signal | B3140 00 | 1 | 1 | -- |
Passenger Door Lock Switch Lock Signal | B3155 00 | 2 | 2 | -- |
Passenger Door Lock Switch Unlock Signal | B3145 00 | 2 | 2 | -- |
Door Lock Actuator Lock Control | 3 | 3 | 3 | -- |
Door Lock Actuator Unlock Control | 3 | 3 | 3 | -- |
Lock PCB Relay Control | B3135 00 | 3 | 3 | -- |
Unlock PCB Relay Control | 3 | B3125 00, B3130 00 | 3 | -- |
Driver Door Lock Switch Ground | -- | 1 | 1 | -- |
I/P Fuse Block Ground | -- | 3 | 3 | -- |
Passenger Door Lock Switch Ground | -- | 2 | 2 | -- |
1. Driver Door Lock Switch Malfunction 2. Passenger Door Lock Switch Malfunction 3. Door Latch Malfunction | ||||
Circuit/System Description
The unlock relays are controlled by the body control module (BCM) through driver door and passenger door low side drive control circuits and the lock relays are controlled through a single high side drive control circuit. During lock or unlock operation, battery voltage will be supplied to the lock actuators through the energized relays and grounded through the de-energized relays.
Conditions for Running the DTC
The system voltage must be between 9-16 volts.
Conditions for Setting the DTC
B3125 00 or B3130 00
The BCM detects a fault in the UNLOCK PCB relay control circuit.
B3135 00
The BCM detects a fault in the LOCK PCB relay control circuit.
Action Taken When the DTC Sets
The power door locks will malfunction.
Conditions for Clearing the DTC
| • | The DTC will be current for as long as the fault is present |
| • | When the fault is no longer present, the DTC will be a history DTC. |
| • | A history DTC will clear after 50 ignition cycles. |
Reference Information
Schematic Reference
Door Lock/Indicator Schematics
Connector End View Reference
Description and Operation
Power Door Locks Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Command the driver door and passenger door latches to LOCK and UNLOCK by using the door lock switch, the doors should perform the LOCK and UNLOCK function.
Circuit/System Testing
- Ignition OFF, disconnect the X7 harness connector at the BCM.
- Ignition ON, test for greater than 9 volts between the control circuit terminal listed below and ground.
- Connect a 15A fused jumper wire between the control circuit terminal 6 and ground. Verify the driver door latch performs the UNLOCK function.
- Connect a 15A fused jumper wire between the control circuit terminal 9 and ground. Verify the passenger door latches perform the UNLOCK function.
- Verify that a test lamp illuminates between the control circuit terminal 7 and B+.
- Connect a 15A fused jumper wire between the control circuit terminal 7 and B+. Verify the door latches perform the LOCK function.
- If all circuits test normal, replace the BCM.
| • | Terminal 6 |
| • | Terminal 9 |
| ⇒ | If less than the specified range, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the I/P fuse block |
| ⇒ | If the driver door latch does not perform as specified, test the control for a short to voltage. If the circuit tests normal, replace the I/P fuse block. |
| ⇒ | If the passenger door latches do not perform as specified, test the control for a short to voltage. If the circuit tests normal, replace the I/P fuse block. |
| ⇒ | If the test lamp does not illuminate, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the I/P fuse block. |
| ⇒ | If the door latches do not perform as specified, test the control for a short to ground. If the circuit tests normal, replace the I/P fuse block |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup and programming |
